diff --git a/extensions/vier-cognitive-voice-gateway/src/helpers/util.ts b/extensions/vier-cognitive-voice-gateway/src/helpers/util.ts
index 50c69011..998f52ff 100644
--- a/extensions/vier-cognitive-voice-gateway/src/helpers/util.ts
+++ b/extensions/vier-cognitive-voice-gateway/src/helpers/util.ts
@@ -110,7 +110,11 @@ function toNumberOrUndefined(numeric: number | string | undefined | null): numbe
     return undefined;
   }
   if (typeof numeric === 'string') {
-    const parsedNumber = Number(numeric);
+    const trimmed = numeric.trim()
+    if (trimmed === '') {
+      return undefined
+    }
+    const parsedNumber = Number(trimmed);
     return isNaN(parsedNumber) ? undefined : parsedNumber;
   }
   if (typeof numeric !== 'number') {
diff --git a/extensions/vier-cognitive-voice-gateway/src/nodes/promptForNumber.ts b/extensions/vier-cognitive-voice-gateway/src/nodes/promptForNumber.ts
index bda4a5d3..ee4b7d95 100644
--- a/extensions/vier-cognitive-voice-gateway/src/nodes/promptForNumber.ts
+++ b/extensions/vier-cognitive-voice-gateway/src/nodes/promptForNumber.ts
@@ -123,6 +123,7 @@ export const promptForNumberNode = createNodeDescriptor({
       });
     }
 
+    const maxDigits = normalizeInteger(config.maxDigits, 1, undefined);
     const payload = {
       status: 'prompt',
       timeout: convertDurationFromSecondsToMillis(config.timeout),
@@ -132,8 +133,8 @@ export const promptForNumberNode = createNodeDescriptor({
       type: {
         name: 'Number',
         submitInputs: submitInputs,
-        minDigits: normalizeInteger(config.minDigits, undefined, undefined),
-        maxDigits: normalizeInteger(config.maxDigits, undefined, undefined),
+        minDigits: normalizeInteger(config.minDigits, undefined, maxDigits),
+        maxDigits: maxDigits,
       },
     };
     api.say(config.text, payload);